Outer member of constant speed universal joint

摘要

An outer member of a constant velocity universal joint suppresses occurrences of cracking in a joining portion and has stable quality. The outer member includes a cup section having track grooves formed therein, and a shaft section having one end coupled to a bottom portion of the cup section. By joining members having different carbon contents and performing induction hardening on the members, a hardening heat-affected portion affected by the induction hardening, a hardening heat-unaffected portion unaffected by the induction hardening, a joining heat-affected portion affected by heat generated during the joining, and a joining heat-unaffected portion unaffected by the heat generated during the joining are formed. A martensitic structure is eliminated from the hardening heat-unaffected portion of the high carbon content member and is the joining heat-affected portion at an end portion including a joining end surface that is to be joined to the low carbon content member.